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close this bookHow to Make? An Improved Soap .. Not just for more Foam (GTZ, 1993, 71 p.)
close this folderC. Saponification of simple fats
View the documentC.I. Peanut oil
View the documentC.II. Copra oil
View the documentC.III. Cotton oil
View the documentC.IV. Shea butter
View the documentC.V. Palm oil
View the documentC.VI. Palmkernel oil
View the documentC.VII. Tallows (cow and mutton)
View the documentC.VIII. Fat (pork)
View the documentC.IX. Neem oil
View the documentC.X. Pourghere oil
View the documentC.XI. Castor oil
View the documentC.XII. Sesame oil

C.V. Palm oil

It is extracted from the pulp of the palm fruit (Elais sp.). Industrial plantation are done in equatorial zones with abundant rains. In humid savannas, the palm tree grow naturally in the valleys along the rivers so that palm oil must be seen as picking product in this ecological zone.

Physical and chemical characteristics:

Density at 15 °C:

0,921 - 0,94

Solidification point:

24 to 30 °C

Iodine:

44 -58

Saponification value:

195 - 205

INS Factor:

137 - 161

Intake in insaponifiable:

< 0,5%

Intake of alkaline solution indicated for saponification (refined oil):

10 to 40 °Be

The sodium soap is hard and of yellow-pale color. It is well soluble in water and slowly forms a lot of stable foam. It has a very good washing power and exerts a very smooth effect on the skin. Unscented, it develops an odor which recalls the oil of origin. It is stable at stockage (doesn't grow rancid).

Palm oil constitutes on of the fat most used in soap-making.

Soap preparation

Pre-treatment

The raw oil has a strong color going from the yellow orange to redbrown. It should then undergo a refining (purification and decoloration) if you want to achieve good colored soaps.

The washing at salted boiling water constitutes a simple means of purification (see technical details of the process in the chapter "peanut oil").

For the bleaching (decoloration) the thermic treatment is a simple method.

It can be implemented as follows:

- Heat raw oil in a wide-opening container up to 200 - 250 °C by stirring from time to time;
- Carry on the operation until a piece of paper which is dipped into the oil doesn't show any coloration.

Saponification

The refined palm oil, according to the above described process, is well appropriate for saponification. To achieve this you use the cold process as well as the semi-hot one.

Recipe:

100 Kg of refined palm oil;
35,50 Kg of caustic soda solution at 15 °Be;
30,65 Kg of caustic soda solution at 40 °Be


Figure

How to conduct the operations

- Weigh the necessary quantity of refined oil and heat it in the boiler to a temperature of 55 - 60 °C;
- Stop the heating and add slowly in small portions the 15 °Be caustic soda solution (formation of emulsion);
- Then add the portion of the strong caustic soda solution (40 °Be) by stirring;
- Stir from time to time and let the temperature decrease progressively;
- Incorporate the additives when the mass gets a temperature of about 55 °C ;
- Then pour the soap into moulds;
- Leave it get cold and hard;
- Take out of the moulds and cut the lumps into bars and pieces.